With its seemingly endless flow of bright meteors visible to the naked eye, the Perseid meteor shower is a favorite among stargazers. So it came as little surprise when NASA officials reported that a recent analysis of data collected over a four year period showed that the annual event is the busiest of its kind.
"We have found that one meteor shower produces more fireballs than any other," Bill Cooke of NASA's Meteoroid Environment Office announced in a statement. "It's the Perseid meteor shower, which peaks on August 12th and 13th."
The finding is based on research that began back in 2008 and included a network of meteor cameras distributed across the southern United States set on tracking fireball activity. The resulting database of hundreds of events, in the end, pointed to the Perseids as the "fireball champion" of annual meteor showers.
The term fireball is used in reference to a meteor at least as bright as Jupiter or Venus when viewed from Earth and can be seen on any given night as random meteoroids strike the Earth's upper atmosphere, colliding with the friction found there.
Clumps of them appear, however, when Earth passes through the debris stream of a comet, as will occur later this month.
Specifically, the Perseid meteor shower comes from Comet Swift-Tuttle and occurs every year in early- to mid-August as Earth passes through the cloud of dust sputtered off the comet in its march toward the Sun. As a result, Perseid meteoroids hit Earth's atmosphere at a speed of 132,000 mph, producing an especially bright and busy show.
The reason the Perseids are so rich in fireballs, Cooke explains, has to do with the size of the parent comet.
"Comet Swift-Tuttle has a huge nucleus -- about 26 km in diameter," he said. "Most other comets are much smaller, with nuclei only a few kilometers across. As a result, Comet Swift-Tuttle produces a large number of meteoroids, many of which are large enough to produce fireballs."
For those eager to get in on the action, the professional stargazer recommends looking heavenward on the nights of August 12 and 13, between 10:30 p.m. and 4:30 a.m. local time.
Though the shower will start slow, Cooke explains that it will pick up as the night wears on, eventually peaking before sunrise when the constellation Perseus is high in the sky.
And while easy to spot in most areas, the scientist encourages people interested in watching the show to stay away from brightly lit areas if they want to experience the event in full detail.
"Get away from city lights," he said. "While fireballs can be seen from urban areas, the much greater number of faint Perseids is visible only from the countryside."
For those that do, Cooke tells people they can look forward to seeing as many as 100 per hour.